Biomechanical evaluation of the effect of mesenchymal stem cells on cartilage regeneration in knee joint osteoarthritis

Abstract

Numerous clinical studies have reported cell-based treatments for cartilage regeneration in knee joint osteoarthritis using mesenchymal stem cells (MSCs). However, the post-surgery rehabilitation and weight-bearing times remain unclear. Phenomenological computational models of cartilage regeneration have been only partially successful in predicting experimental results and this may be due to simplistic modeling assumptions and loading conditions of cellular activity. In the present study, we developed a knee joint model of cell and tissue differentiation based on a more mechanistic approach, which was applied to cartilage regeneration in osteoarthritis. First, a phenomenological biphasic poroelastic finite element model was developed and validated according to a previous study. Second, this method was applied to a real knee joint model with a cartilage defect created to simulate the tissue regeneration process. The knee joint model was able to accurately predict several aspects of cartilage regeneration, such as the cell and tissue distributions in the cartilage defect. Additionally, our results indicated that gait cycle loading with flexion was helpful for cartilage regeneration compared to the use of simple weight-bearing loading.